I have a 2005 GTX 4 Tec No Blower it has 78 actual hours on it and has been adult driven since new. When you run it about 30 MPH at about 4500 RPM it will surge up and down varying about 350 rpm, run it faster or slower it runs fine, I changed the plugs but no difference, it isn't an ignition issue, more like a fuel or throttle issue, possible vacum leak ?? Any suggestions appreciated Thanks Terry.
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